Recent advances in photocatalytic water splitting reactions, especially under visible light irradiation, are reviewed here. In line with such work, the development of various unique photocatalysts including cation or anion-doped metal oxides or metal oxynitride has been introduced. Special attention is focused on the preparation of visible light-responsive TiO2 thin films by a RF-magnetron sputtering method and their applications for the separate evolution of H-2 and O-2 from water under visible or solar light irradiation. (c) 2007 Elsevier B.V. All rights reserved.